Draft gear



April 26,1932. 'w. H. COTTON DRAFT GEAR Filed Spt. 2 2, 192: s Sheets-Sheet 1 1% yen to):

April 26, 1932. w. H. CQmN 1,855,514

DRAFT GEAR Fil p 22, 1925 5 Sheets-Sheet 2 iim April 26, 1932; I w. H. COTTON 1,855,514

DRAFT GEAR Filed Sept. 22, 1923 S Sheets-Sheet 5 [91 yen for jfaZZer/Vearz Patented Apr. 26, 1932 i WALTER'H. common, on -CHIGAGO,ILLINOIS, ASSIGNOR To .fiNIONf DRAIji GEARflb I PANY OF enrolle -rumors, "A oonroansrronon -nnmwirnnn':. .31?

" DRAFT GEAR. L

Ap cation filed September 22, 1923.; Serial no. 4,141; f T

The invention relates Qtddrait gears' orshock absorbing devices for, railway cars, and

is of the so-called friction type in which the A shocks incident to the pulling or buffing ac= tions are largely absorbed by the friction between relatively'movable parts. More specifically, the invention relates to-that typeof friction gears which include relatively movable intercalating plates with wedging means for squeezing them together. i

The principal object of the invention is to secure high efficiency. Other objects and advantages'will be apparent in connection wlth the description, manner of installing, and

tion through the gear," andshowing in elevation a detail of the coupler andapart'ofthe underframing of the car; V c

Fig; 3 is a sectional'view of the gear on the line 3-3 of Fig.1; V Fig. 4: is a view similar to Fig. 1, the gear being shown fully compressed by-fa buffing action; V

- Figs; '5, 6 and 7 are views in'persp'ective of various wedging elements used in the gear;

Fig. 8 is a detail of aspringseatused in the gear, and of the part to 'which it is anchored.

Inthe drawings there are shown portions of a pair of center or draft sills" 10, .10, to each of which there isattached a suitable draft lug 11, 11, and a bulfing luglQ, 12. The" butt of the'coupler is shown at 13, and its extension or yoke element at'l l. This yoke is shown'as in thecommonform' of a loop for inclosing the gear. r

Follower plates 15, 16, inclosed within the yoke 14, cooperate, respectively, withjthe draft and buffing lugs. A pair of box-like casings 17,18, are housed within the yoke,-

one being adjacent 5 to "each? of the follower plates but-normally spaced therefrom. Each or" these casings is provided with an'endwallf adapted to be engaged 'fbyfthe "adj acefntfOl'. lower plate, and with top', "bottomend", s e walls: The-length of 1 these casings such that their *innerfends come into con ct tfij: limitthe compressivemovenient ofithe and prevent injury of its'springs Slots, *as 19; are formed longitudinally; 1n the side "walls of eachi of' the. casings; and through'tlie slots ofeach casing,a'Iid'tliriiigli suitable slots, as shown at 20', in the sills 110;"

extend-bars 21'; 22, between theendfportfions 1 of which there react helical sprin'gs 23, 24.: 65" Preferably, as shown, these springelements eachcom'prises "a pair-of nested springsfl fAei' suitable 'seat,'as 25', '26,'is applied'to eaclik-"lngl of each 'spring and bears directly against H the bar with which it is associated, and to 7b which bar it is securedbyapinforbolt,as"27,

in order-to prevent its lateral displacement:

By associating-thespringelementswith-the end portions of the transverse bars-thwart located outsideof' the car silIs, and'co'nse;v

quently leave' the entire cross 'section at the yoke-inclosed portion of thegear-availablefor the frictionand wedging elements.

' Two groups of relatively movable ir'ltercalating plates} are housed within the ca'singjs' so 17 18,- on opposite sidesof the-axis of the; gear, these; groups beinggeneraily designat ed bythe numerals 28, 29. Eachgroup of plates'is'located adjacent to 1the orr s 6nd i ing sidewa'llfof the casingl'l, 18, and be tween the two groups are interposed the wedging elements. v f 3 Each group of plates "comprises twosetsf as 30, 31, thejone set "normally extending from, or approximately; froin,- the end-jwall of thejcasingl7, and the other set from, or} approximately from, th end wallofthe case ing 18. The length of these plates is pref? er'ably such that in :the normal; 'po'sition 'of the gear they are slightly outer contact-with; the endwall ofthe casing to which 'theyare'i' adj acent, and will not come into Contact with the end*wallof ;the 1 other fca'sing when the" gear is 'fu lly ;compressedi-* The pia'tes are slotted, as hown Meagan, in what ma *b 16b i the groups 28, 29,'are two pairs of opposed wedgingfishoes34, 35, and 36, .37." .These shoes are identical in"form,';one"'of them being shown, removed from the gear, in Fig; 6'. Each of these shoes comprises a flat base plate,

for engagement with the inner friction plate, and instanding wedge members '38, 39, the

front and rear faces of which are inclined to I theaizis of the gear in opposite directions, as shownat 40, 41. Each of theseplates overlaps oneof the bars 21, 22, and is slotted, as shown at 42, to receive the same. 'Interposed between the outer wedging faces of each pairof the shoes and the adjacent follower plate 15, 16, is a wedge-block 43, one of which is shown in Fig. 7 separated from the gear, the end wall of theadja'cent casing 17 or 18 beingapertured to accommodateiit and to allow free relative movement of the casing and block. 7

Cooperating with the inner faces 41 of each 9 pair of the shoes is a wedge-block 44,0ne of which is shownin Fig. 5removed from the gear. Each of these blocks is provided with a shank 45, slotted, as shown at 46, to receive the adjacent bar 21 or 22; the length of the slotbeing'somewhat greater than the width of the bar for convenience in assembling.

The inner end of each ofthe wedge-blocks- 43' is slotted, as shown at 47 to loosely receive the stem of the adjacent block 44.

, Normally the parts occupy the relative po'- sitions as shown in Fig. 1; thefollower plates 15, 16, being in engagement, respectively,

with the draft lugs 11 and bufiing lugs 12;

the casings 17 18, are each rspaced a short distance from the adjacent follower plate,

the; outer end of each'of theslots 19 engaging'the bar 21 or 22; theends ofeach set of thetwo groups of friction plates are spaced a short distance from the end wallof one of the casings 17, 18; the wedge-blocks 43, 43, are in bearing each upon one of the follower plates and the outer wedging faces 40 of the pairof friction shoes with which it cooperates; each of the wedging blocks 44 is in engagement with the inner faces 41 of the wedg- 1ng shoes;and the bars 21, 22, are spaced frlom the adjacent ends ofthe slots20 in the si ls. '1

Upon the application ofbufiing stresses the .9: follower 15- is moved backwardly, carrying with it theassociatedwedge element 43,which, actingvupon the shoes 34, 35, tends to spread and advance them. This advance movement carries forward the element44, withlwhich Q this-pair of-shoes is associated, and with it the bar: 21, which moves away from the ends of the "slots in the casing 17, putting the springs 23, 24, under compression and moving backwardly the bar 22. This bar carries with it the casing 18 and the rearward element 44, the latter moving backwardly and spreading the shoes 36, 37. When the follower plate 15 engages the casing 17, the latter is moved backwardly, carrying with it the plates 3O.v The plates 31 move backwardly into .engagementwith the end wall of the casing 18, and come to rest when this casing engages the follower 16, the plates 30 continuing to advance; The compressive move ment may continue until the parts reach the position shown-in Fig. 4. Upon relief of the pressureupon the'plate 15 the gear is released under theaction of the springs 23, 24, and by the cooperation of the several wedging ele ments, the inclinationof the wedging faces to the axis of the gear being greater than the angle of repose,

p In draft theaction is thesame as in buffing, except, of course, that the movement of the parts is in the opposite direction. The re sistance of the gear to compressing forces gradually and continuously increases as these forces are applied. The form and arrangement of parts are such that a large number of friction plates may be employed, and the gear has very high capacity and great dura bility. g

While a preferred form of construction is shown, various changes may be made within the scope of the invention. The spring seats 25 are shown as provided with apertured lugs 48, 49, for the accommodation of retaining bolts (not shown), which may be inserted .andform convenient means for compressing the springs to facilitate the assembling of the gear.

I claim as my invention 1, In a draft ear, in combination, a pair of opposed cham ered casings, two groups of intercalating friction plates housed within the casings, two pairs of opposed shoes interposed between .the twogroups of plates each shoe having oppositely inclined wedging faces, a spreading wedge at each end of the gear engaging the outer wedging faces'of 1:15 each pair of shoes, a wedging element engag ing the inner wedging faces of each pair ofshoes, such last-named wedging elements each having a transversely aperturedstem proj ecting toward the adjacent end of the gear, a pair of bars extending transverselythrough the casings and stems, and compression springs interposed between the end portions of the two bars.

2. In a draft gear, in combination, a casing having side walls, intercalating plates: inclosed within the casing, wedging means forcompressing the plates, a pair of bars extending transversely through the gear and engageable with the wedging means for hold- 130 ing the elements thereof in cooperative relation and with the plates for effecting their withdrawal on release, and springs reacting between the end portions of the bars.

3. The combination in a draft gear, of a pair of opposed chambered casings, twopairs of opposed friction shoes each having op- I p'ositely inclined wedging surfaces positioned transversely apertured stem projecting to 7 ward the adjacent end of the said gear, a pair of bars extending transversely through the casings and stems, and compression springs interposed between the end portions of the 7 two bars.

4. A draft gear comprising a pairof fol lowers, a group of relatively movable intercalated friction plates, means including plate engaging shoe members and shoe engaging wedge members at each end of the gear for forcing said plates laterally, meansfor limiting the lateral movement of said plates, means including resilient elements located wholly outwardly of said plates for resisting the in-' ward movement of said wedge members, said means engaging one of said wedge members at each end of the gear for releasing said wedge members upon the initial release movement of said gear and for returning said plates to inoperative position during the final release movement of said gear, one of said wedge members at each end of the gear having its wedge faces forming an acute angle and converging outwardly toward the end of the gear. 7

5. In a draft gear, a plurality of interealated friction plates, retracting members to which said plates are connected, resilient means between said members, friction shoes in engagement with said plates, lateral pressure creating means engaging said shoes for forcing the same laterally into frictional contact with said plates, said means including wedging elements connected to said members and tapered toward the adjacent ends of said gear respectively, and means for resisting the lateral pressure of said plates.

6. In a draft gear, a plurality of intercalated friction plates, means including fric tion shoes, a bar, and a wedge member at each end of the gear for creating lateral pressure on said plates when said gear is compressed, said wedge members being connected to said bars and having their backs turned toward each other, means for resisting the lateral pressure of said plates, and means for resisting the longitudinal inward movement of saidwedges upon the compression of the gear and for restoring the parts to normal position after compression.v

7 In a draft gear, two sets of intercalated sisting the movement of saidbars toward each friction plates, a retracting bar connected Y with each set of plates, spring means for rea other, friction shoes in frictional contact with said plates at the ends thereof, wedging mechanism operated by the compressionof said gear for forcing said shoes into frictional contactwith said plates, and means for resisting the lateral pressure of saidshoes, said j mechanism including a wedge member engaging each bar at each end of the gear and having its wedging faces forming'an acute angle located between said bars. 7

WALTER H. COTTON. 

